Technical Article

IPv6 Does Not Mean The End of IPv4

I know I’ve touched on this topic in some of my “IT Management” overview blogs, but it’s an important one, so I thought I’d give it a blog all its own.

Even though we have a living myth that cats and dogs never get along, we all know it just isn’t true. There are any number of cats and dogs that live together and do just fine – including our two, Sun Tzu (Dog) and Nietzsche (Cat). While we all enjoy the joke, we know that deep down, the two are compatible, and it really is just a fun myth to keep alive.

The same is true of IPv4 and IPv6. Like cats and dogs compete for resources around the house, IPv4 and IPv6 give the appearance of being incompatible around the datacenter. But like a cat and dog will work out a pecking order that works for them to insure both receive a sufficient amount of resources (primarily food and treats), the technology marketplace has worked out a slew of solutions that allow IPv4 and IPv6 to work together. From F5’s IPv6 Gateway product to Open Source instructions for making an IPv6 gateway out of a Linux box, you don’t have to choose.

Sun Tzu and Nietzsche early in life

The point of these products is to translate between the two protocols to make certain that incoming and outgoing messages are correctly formatted for their recipients, but that’s not a very exciting description. What is exciting is the idea that you can put an IPv6 address on the Internet, and translate incoming packets to IPv4 before they reach your servers. That means you can support IPv6 in the place that matters – on the public Internet, where you have to share the shrinking number of IPv4 addresses or move to IPv6 – and not change every server in your datacenter at once. That’s huge, because upgrading every machine in your datacenter would be painful to say the least. While it might just come off without a hitch, it might not.

Another great benefit is that you don’t have to drop support for IPv4 to support IPv6. That matters a lot, because many clients out there don’t yet support IPv6, but the future will definitely belong to the newer technology, just because we need the new address space. Utilizing a gateway, you can support both until IPv6 is ubiquitous, then slowly turn off IPv4 support.

So the short summary – with an IPv6 gateway, you can serve your current customers, prepare for serving future customers, and not change your entire datacenter over a single weekend… If you’re lucky enough not to have problems doing so anyway.